Heating/cooling systems with hydronic emitters (including radiators, underfloor heating/cooling circuits, fan coils, chilled beams) are based on power transfer from one or more of the hydronic emitters to affect one or more environmental entities (for example, offices, apartments, conference rooms, and the like). Traditional approaches often modulate the flow temperature directly from the boiler, where only a single available modulated output is available. Traditional approaches may support two separate heating outputs, but costs increase dramatically with dual outputs. Consequently, with traditional approaches multiple heating zones for a building may be economically impracticable. Moreover, in accordance with traditional approaches, a special modulating heat source (for example, a boiler) may be required. Achieving a low flow temperature, as may be required during times when the outside weather conditions are mild (such as during the spring and autumn), cannot normally be achieved with flow temperature directly from the boiler. This limitation results in the modulating thermostatic control having to revert to “on/off” control rather than using modulating control when a low-load situation is encountered due to the modulating boiler being incapable of modulating down to low flow temperatures.